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21.
BackgroundOne-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.MethodsThirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m2; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.ResultsThere were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).ConclusionThe results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity.  相似文献   
22.
在分布式系统应用中采用动态负载平衡算法分配系统中的工作负载,能够显著地提高系统的性能。针对分布式系统中负载动态变化特性,提出了一种基于接收者主动的自索取动态负载均衡算法,通过负载数的实时变化反映系统中各节点的当前负载状况,通过空闲节点来转移超载节点的任务,使负载的分布更均匀,提高了整个系统资源的利用率及效率.  相似文献   
23.
针对新兴的工程网络计划技术采用逆向思维,在网络计划优化中对于工期优化采用“TFE”法进行优化的新思路,使网络计划工期的优化较为简便.  相似文献   
24.
吴红波  郭忠明  毛瑞娟 《资源科学》2012,34(12):2289-2298
在全球气候变暖的背景下湖泊变化已是国内外地学界关注的环境问题,并日益受到各国政府和研究机构的重视。本文以长江中下游的6个典型湖泊为研究对象,基于2003年-2009年ICESat—GLAS测高数据,采用高斯滤波法对ICESat—GLAS测高数据所对应的回波进行去噪后,用于识别水体与陆地;采用融合算法从LandsatTM影像数据提取湖泊边界;提取湖泊边界内的ICESat—GLAS水位观测值构建了湖泊的年际和年内水位变化,进一步分析了6个湖泊的水位变化时空特征与原因。结果表明:从LandsatTM中提取湖泊边界的精度达到10m,ICESat—GLAS测高数据推算出洪泽湖蒋坝站、洞庭湖城陵矾站、鄱阳湖星子站和都昌站、太湖西山观测站、巢湖闸站和高邮湖高邮站的ICESat测高数据验证的平均精度分别为-3.9cm、-8.3cm、-9.0cm、-2.5cm、-3.1cm和-4.1cm;在整个观测期间,长江中下游流域的湖泊水位呈周期性波动,但较历史观测资料,湖泊平均水位有所降低,且自2006年10月以后三峡工程对洞庭湖的水位调控明显。  相似文献   
25.
采用文献资料、问卷调查等研究方法,对苏州地区11所普通高校800名大学生,就其体育生活形式、内容及其时空结构取舍进行调查分析。结果显示,大学生体育生活形式呈现多元化趋势,体育活动的时间主要集中在下午至晚上课余时间,在校园内的一些免费场馆进行体育锻炼;在活动项内容上,男生参与较多的为三大球,女生则以体操类活动为主,小球居次,一些休闲性、时尚性、娱乐性的项目逐渐成为当代大学生体育生活的一部分。  相似文献   
26.
采用MCA-3C心脏功能综合检测仪,观察男子中长跑运动员在功率自行车上进行递增负荷运动时心脏收缩时间间期各指标的变化,并与非运动员进行比较,从而对中长跑运动员的左心功能进行系统评价。结果发现:安静及递增负荷运动过程中中长跑运动员LVET和PEP相对较长;递增负荷运动过程中,中长跑运动员心脏功能表现出优于普通大学生的心脏功能水平。  相似文献   
27.
The influence of preparation time on ankle joint biomechanics during highly dynamic movements is largely unknown. The aim of this study was to evaluate the impact of limited preparation time on ankle joint loading during highly dynamic run-and-cut movements. Thirteen male basketball players performed 45°-sidestep-cutting and 180°-turning manoeuvres in reaction to light signals which appeared during the approach run. Both movements were executed under (1) an easy condition, in which the light signal appeared very early, (2) a medium condition and (3) a hard condition with very little time to prepare the movements. Maximum ankle inversion angles, moments and velocities during ground contact, as well as EMG signals of three lower extremity muscles, were analysed. In 180°-turning movements, reduced preparation time led to significantly increased maximum ankle inversion velocities. Muscular activation levels, however, did not change. Increased inversion velocities, without accompanying changes in muscular activation, may have the potential to destabilise the ankle joint when less preparation time is available. This may result in a higher injury risk during turning movements and should therefore be considered in ankle injury research and the aetiology of ankle sprains.  相似文献   
28.
The present study examined the generalizability of the factor pattern, structural parameters, and latent structure of a multidimensional hierarchical model of ethnocultural empathy in males and females. The Scale of Ethnocultural Empathy (SEE) (Wang et al., 2003) was administered to a sample of 610 Italian undergraduates to examine the generalizability and reliability of its factor structure across gender, the psychometric properties and the validity of the scale. Two models were tested through multi-group confirmatory factor analysis (MGCFA): a confirmatory factor-analytic model that hypothesized a multidimensional model of ethnocultural empathy; and a structural equation model that proposed a multidimensional, hierarchical structure with global ethnocultural empathy as a superordinate construct that explained the covariances among the subdomains of the SEE. Both models satisfied multiple criteria for goodness-of-fit with the data. Full metric invariance of factor loadings and factor covariances, and partial invariance of error variances across gender for the four-factors model were supported. Scale reliability was also satisfactory, showing good internal consistency. As regard scale validity, evidence was found for a positive moderate association with a measure of general empathy and a negative high association with a measure of prejudice. Implications are discussed.  相似文献   
29.
An experimental 2 (channel) × 2 (gender) × 3 (time) mixed factorial design (N = 159) was applied to test and compare how individual dimensions of intercultural sensitivity might be affected by two channels: a virtual environment (i.e., Second Life®) versus a Web environment. Using a modified version of Chen and Starosta's Intercultural Sensitivity Scale (ISS), the study sought to identify which of the five ISS dimensions played the most influential role in intercultural sensitivity outcomes: interaction enjoyment, interaction engagement, interaction confidence, interaction attentiveness, or respect for cultural differences. Results showed that one's willingness and effort toward understanding an intercultural interaction – interaction attentiveness – played the greatest and most statistically significant role in intercultural sensitivity outcomes, and that this effect was greatest within the virtual environment channel. Gender effects were also found, in which men experienced greater enjoyment but women expressed more attentiveness.  相似文献   
30.
我国举证时限制度的价值分析及完善   总被引:1,自引:0,他引:1  
举证时限制度作为民事证据的一项基本制度,有利于诉讼证明任务的完成和举证责任的落实,有利于程序公正的实现,有利于诉讼效率和效益的提高及程序的安定.综观中外举证时限制度的有关规定,其既有共同之处,也存在明显差异.我们需要在总结司法实践经验的基础上,借鉴两大法系的有效做法,进一步完善我国的举证时限制度.  相似文献   
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